Lenze PLC Designer PLC Designer (R2-x) - Manual (Page 560)

L-force | PLC Designer
Siemens Import
558 DMS 3.2 EN 02/2011 TD29

• There are also firmware OBs that have no interface but whose code is in 805xx
Assembler (as an example) and not in STEP5. This mainly affects the PID regulator
listed as OB251 which obtains its parameters and local variables through a
separate (data) block that you can select. Neither the PID regulator, the
corresponding data block or other POUs that use regulators to access the data
block can be converted to IEC. The IEC code that is created for data blocks and
other POUs during the conversion is meaningless without the PID regulator. The
meaning of the individual program parts can be found in the programming
handbook for the CPU.
• Configuration data blocks (like DB1 [S5-95U], DX0, and DX2) are sometimes used
to configure S5 CPUs and other assemblies that were converted into useless IEC
POUs. The meaning of much of this type of data can be found in the programming
handbook for the CPU. For the rest you must use a S5 programming system that
can evaluate the configuration DBs . The configuration affects settings for
communication, analog value processing, multiprocessing, etc. Therefore, it is
useless to even think about working with these POUs on a non-Siemens SPS.
Once the import is complete, you have to find the errors that are shown and then fix,
add to and rewrite the affected spots. These spots are marked with comments like:
(*Warning! Unconvertible STEP5/7 code shown as comment:*)
This is followed by the unconvertible code which is also shown as a comment.
Finally, you must check the addresses. Original Siemens addresses are created during
the import. These addresses have the following format:
Bits: Byte-Offset.Bit-Nummer
Non-Bits:Byte-Offset
Also word addresses that follow each other in sequence will overlap (simply due to the
fact that the numbers in the addresses are byte offsets). This means that %MW32 and
%MW33 have an overlapping byte which is %MB33 (only on a Siemens SPS). On your
SPS, %MW32 and %MW33 would not normally have anything to do with each other.